Search Results (319)

A novel centrifuge-less cloud point extraction (CL-CPE) method was developed for the spectrophotometric determination of copper(II) using 4-nitrocatechol (4NC) as the chelating agent. The extraction system utilizes a mixed micellar phase composed of the nonionic surfactant Triton X-114 and the ionic liquid (IL) Aliquat^® 336 (A336). The extracted ternary ion-association complex, identified as (A336⁺)₂[Cu(4NC)₂], exhibits a maximum absorbance at 451 nm, with a molar absorption coefficient of 8.9 × 10⁴ M⁻¹ cm⁻¹ and a Sandell’s sensitivity of 0.71 ng cm⁻². The method demonstrates a linear response in the copper(II) concentration range of 32–763 ng mL⁻¹ and a limit of detection of 9.7 ng mL⁻¹. The logarithmic extraction constant (log K_ex) was determined to be 7.9, indicating efficient extraction. Method performance, evaluated by the Blue Applicability Grade Index (BAGI) and the Click Analytical Chemistry Index (CACI), confirmed its feasibility, practicality, simplicity, convenience, cost-effectiveness, environmental friendliness, and analytical competitiveness. The proposed IL-CL-CPE method was successfully applied to the analysis of a dietary supplement, a solution for infusion, and synthetic mixtures simulating various copper alloys. Full article

The electrooxidation (EO) of three important environmental contaminants, anticorrosive 1H-benzotriazole (BTA), plasticizer dibutyl phthalate (DBP), and non-ionic surfactant Triton X-100 (tert-octylphenoxy[poly(ethoxy)] ethanol, t-OPPE), was studied as a possible means to improve their elimination from wastewaters, which are an important emission source. EO was performed in a batch reactor with a boron-doped diamond (BDD) anode and a stainless steel cathode. Different supporting electrolytes were tested: NaCl, H₂SO₄, and Na₂SO₄. Results were analysed from the point of their efficacy in terms of degradation rate, kinetics, energy consumption, and transformation products. The highest degradation rate, shortest half-life, and lowest energy consumption was observed in the electrolyte H₂SO₄, followed by Na₂SO₄ with only slightly less favourable characteristics. In both cases, degradation was probably due to the formation of persulphate or sulphate radicals. Transformation products (TPs) were studied mainly in the sulphate media and several oxidation products were identified with all three contaminants, while some evidence of progressive degradation, e.g., ring-opening products, was observed only with t-OPPE. The possible reasons for the lack of further degradation in BTA and DBP are too short of an EO treatment time and perhaps a lack of detection due to unsuitable analytical methods for more polar TPs. Results demonstrate that BDD-based EO is a robust method for the efficient removal of structurally diverse organic contaminants, making it a promising candidate for advanced water treatment technologies. Full article

This study presents research on the production of activated biocarbons derived from herbal waste. Sage stems were chemically activated with two activating agents of different chemical natures—H₃PO₄ and K₂CO₃—and subjected to two thermal treatment methods: conventional and microwave heating. The effect of the activating agent type and heating method on the basic physicochemical properties of the resulting activated biocarbons was investigated. These properties included surface morphology, elemental composition, ash content, pH of aqueous extracts, the content and nature of surface functional groups, points of zero charge, and isoelectric points, as well as the type of porous structure formed. In addition, the potential of the prepared carbonaceous materials as adsorbents of model organic (represented by Triton X-100 and methylene blue) and inorganic (represented by iodine) pollutants was assessed. The influence of the initial adsorbate concentration (5–150 (dye) and 10–800 mg/dm³ (surfactant)), temperature (20–40 °C), and pH (2–10) of the system on the efficiency of contaminant removal from aqueous solutions was evaluated. The adsorption kinetics were also investigated to better understand the rate and mechanism of contaminant uptake by the prepared activated biocarbons. The results showed that materials activated with orthophosphoric acid exhibited a significantly higher sorption capacity for all tested adsorbates compared to their potassium carbonate-activated counterparts. Microwave heating was found to be more effective in promoting the formation of a well-developed specific surface area (471–1151 m²/g) and porous structure (mean pore size 2.17–3.84 nm), which directly enhanced the sorption capacity of both organic and inorganic contaminants. The maximum adsorption capacities for iodine, methylene blue, and Triton X-100 reached the levels of 927.0, 298.4, and 644.3 mg/g, respectively, on the surface of the H₃PO₄-activated sample obtained by microwave heating. It was confirmed that the heating method used during the activation step plays a key role in determining the physicochemical properties and sorption efficiency of activated biocarbons. Full article

The treatment of type 1 diabetes through pancreatic islet transplantation faces significant limitations, including donor organ shortages and poor islet survival due to post-transplantation loss of extracellular matrix support and inadequate vascularization. Developing biocompatible scaffolds that mimic the native islet microenvironment could substantially improve transplantation outcomes. This study aimed to create and evaluate decellularized (DCL) matrices from porcine organs as potential platforms for islet transplantation. Porcine lung and pancreatic tissues were decellularized using four different protocols combining detergents (Triton X-100, SDS and SDC) with optimized incubation times. The resulting matrices were characterized through DNA quantification and histological staining (H&E and Van Gieson). Islet viability was assessed in vitro using Live/Dead staining after 3 and 7 days of culture on the matrices. In vivo biocompatibility was evaluated by implanting matrices into rat omentum or peritoneum, with histological analysis at 1-, 4-, and 8 weeks post-transplantation. Protocols 3 (for lung tissue) and 4 (for pancreas tissue) demonstrated optimal decellularization efficiency with residual DNA levels below 8%, while preserving the collagen and elastin networks. In vitro, islets cultured on decellularized lung matrix had maintained 95% viability by day 7, significantly higher than the controls (60%) and pancreatic matrix (83%). The omentum showed superior performance as an implantation site, exhibiting minimal inflammation and fibrosis compared to the peritoneum sites throughout the 8-week study period. These findings establish DCL as a promising scaffold for islet transplantation due to its superior preservation of ECM components and excellent support of islet viability. This work provides a significant step toward developing effective tissue-engineered therapies for diabetes treatment. Full article

A novel, environmentally friendly cloud point extraction (CPE) method based on 4-nitrocatechol (H₂L) was developed in this study to spectrophotometrically determine trace vanadium. This method utilizes a mixed micelle-mediated system comprising a cationic surfactant (cetylpyridinium chloride, CPC) and a nonionic surfactant (Triton X-114). In contrast to conventional CPE, the present approach does not employ centrifugation to separate the two phases. The distinguishing characteristic of the extracted species, (CP⁺)[V^VOL₂], is its ability to absorb light across the entire visible spectrum. The measurement at 670 nm, where the complex displays a local maximum, is advantageous for two primary reasons. Firstly, the blank exhibits virtually no absorption, a property that engenders stable and reproducible results. Secondly, selectivity is high because almost all other metal complexes have absorption bands at shorter wavelengths. The proposed method has the following characteristics: a linear range of 2–305 ng mL⁻¹, a limit of detection of 0.6 ng mL⁻¹, a molar absorptivity coefficient of 1.22 × 10⁵ M⁻¹ cm⁻¹, a Sandell sensitivity of 0.42 ng cm⁻², and a blue applicability grade index (BAGI) of 67.5. Its efficacy was demonstrated in the analysis of mineral water, a spent vanadium-containing catalyst, and a dietary supplement. Full article

This study aimed to characterize and evaluate the fibrinolytic, thrombolytic, hematological, and toxicological aspects of a serine protease (AsKSP) from Aspergillus tamarii Kita UCP 1279. The enzyme was purified using a two-phase aqueous system and assessed for optimal pH (7.0) and temperature (50 °C), stability, and effects of metal ions, inhibitors, and surfactants. AsKSP exhibited stability for up to 120 min at 50 °C and 36 h at pH 7.0. Enzymatic activity was enhanced by Na⁺ and Zn²⁺ and non-ionic surfactants (Tween-80) but inhibited by Cu²⁺, Fe³⁺, Triton X-100, and SDS, reducing activity by up to 62.35%. The highest amidolytic activity was observed for the substrate N-succinyl-Gly–Gly–Phe-p-nitroanilide. SDS-PAGE analysis indicated an approximate molecular mass of 90 kDa. The enzyme showed fibrinolytic activity, degrading 38.81% of fibrin clots in vitro after 90 min, without affecting fibrinogen. Cytotoxicity assays indicated no toxicity (cell viability > 80%). Coagulation assays showed slight prolongation of prothrombin time (PT) and activated partial thromboplastin time (aPTT), with no effect on thrombin time. No red blood cell lysis was observed, and albumin increased enzymatic activity by 31.70%. These findings demonstrate that Aspergillus tamarii Kita UCP 1279 produces a fibrinolytic protease with potential for thrombus treatment, providing a promising foundation for drug development. Full article

Tick-Borne Encephalitis Virus (TBEV) is impacting public health in the Eurasian region, with increasing case numbers. There is, therefore, a need to expand research efforts and the corresponding infrastructure capacity. Since TBEV is classified as a risk group 3 organism in Switzerland, handling infectious material containing the virus is restricted to biosafety level 3 laboratories. In some instances, downstream analyses may need to be performed outside of the containment facility. It is, therefore, essential to validate effective inactivation protocols compatible with the safe and accurate processing of samples. This study evaluated UV irradiation, chemical treatment with detergents, and mechanical filtration as candidate methods to inactivate TBEV infectious samples, including culture supernatants and tissue homogenates, while preserving their compatibility for different assays. Among the methods tested, 45 s of UV irradiation or Triton-X100 at concentrations between 0.05% and 0.1% effectively inactivated TBEV while mostly preserving the integrity of the processed samples for immuno- or enzymatic assays. These findings establish safe and reliable procedures for advancing TBEV research beyond high-containment settings. Full article

The periodate/hydrogen peroxide (PI/H₂O₂) system is a recently developed advanced oxidation process (AOP) characterized by its rapid reaction kinetics, making it highly suitable for continuous-flow applications compared to conventional batch systems. Despite its potential, no prior studies have investigated its performance under flowing conditions. This work presents the first application of the PI/H₂O₂ process in a tubular microreactor, a promising technology for enhancing mass transfer and process efficiency. The degradation of textile dyes (specifically Basic Yellow 28 (BY28)) was systematically evaluated under various operating conditions, including reactant concentrations, flow rates, reactor length, and temperature. The results demonstrated that higher H₂O₂ flow rates, increased PI dosages, and moderate dye concentrations (25 µM) significantly improved degradation efficiency, achieving complete mineralization at 2 mM PI and H₂O₂ flow rates of 80–120 µL/s. Conversely, elevated temperatures negatively impacted the process performance. The influence of organic and inorganic constituents was also examined, revealing that surfactants (SDS, Triton X-100, Tween 20, and Tween 80) and organic compounds (sucrose and glucose) acted as strong hydroxyl radical scavengers, substantially inhibiting dye oxidation—particularly at higher concentrations, where nearly complete suppression was observed. Furthermore, the impact of water quality was assessed using different real matrices, including tap water, seawater, river water, and secondary effluents from a municipal wastewater treatment plant (SEWWTP). While tap water exhibited minimal inhibition, river water and SEWWTP significantly reduced process efficiency due to their high organic content competing with reactive oxygen species (ROS). Despite its high salt content, seawater remained a viable medium for dye degradation, suggesting that further optimization could enhance process performance in saline environments. Overall, this study highlights the feasibility of the PI/H₂O₂ process in continuous-flow microreactors and underscores the importance of considering competing organic and inorganic constituents in real wastewater applications. The findings provide valuable insights for optimizing AOPs in industrial and municipal wastewater treatment systems. Full article

A novel method for the spectrophotometric determination of trace amounts of molybdenum has been developed. This method utilizes a centrifuge-less cloud point extraction (CL-CPE) in a mixed micellar (MM) system containing a nonionic surfactant (Triton X-114) and an ionic liquid (Aliquat^® 336, A336). The chromophore chelating reagent employed was 4-nitrocatechol (4NC, H₂L). This work marks its first application as a CPE reagent. Under the optimal conditions, Mo(VI) forms a yellow ternary complex with 4NC and A336, which can be represented by the formula (A336⁺)₂[MoO₂L₂]. The method possesses the following characteristics: limit of detection (LOD) of 3.2 ng mL⁻¹, linear range of 10.8–580 ng/mL, absorption maximum of 435 nm, molar absorptivity coefficient of 3.34 × 10⁵ L mol⁻¹ cm⁻¹, and Sandell’s sensitivity of 0.29 ng cm⁻². The method has been successfully employed for the determination of molybdenum in reference standard steel samples, bottled mineral water, and a molybdenum-containing dietary supplement. Full article

Vascularized composite allotransplantation (VCA) has emerged as a robust alternative for addressing anatomically complex defects but requires a toxic lifelong immunosuppressive regimen. Tissue engineering offers the promise of creating recipient-specific alternative grafts using a decellularization and recellularization approach. In this article, we establish a reliable protocol for human face decellularization by immersion as a new tool in the development of engineered graft alternatives for reconstructive surgery. Three cadaveric face grafts were immersed in 1% sodium dodecyl sulfate for 216 h followed by 1% Triton X-100 for 48 h, without perfusion through the pedicle. We determined that decellularization was successfully accomplished for three facial specimens as confirmed by histological evaluation and quantification of DNA content. The extracellular components including collagen, glycosaminoglycans, elastin, and matrix-bound growth factors were preserved. Vascular architecture did not show significant differences between native and decellularized grafts as imaged by X-ray angiography. The mechanical strength of the grafts was not altered after decellularization. We also showed that the decellularized grafts were biocompatible in vitro and in vivo allowing cell engraftment. As a result, we have successfully developed a protocol to yield a clinical size decellularized graft suitable for generating a recellularized, potentially non-immunogenic graft for facial reconstruction. Full article

Beryllium (Be) is one of the most toxic non-radioactive elements on the periodic table, and its presence or intake can negatively impact both the environment and human health. Classified as a carcinogen, Be is dangerous even at trace concentrations, stressing the necessity of developing reliable methods for quantifying it at very low levels. Spectrometric techniques for quantifying Be vary in sensitivity and applicability, with inductively coupled plasma mass spectrometry (ICP-MS) being the most sensitive for ultra-trace analysis. Flame atomic absorption spectrometry (FAAS) is suitable for higher Be concentrations, but preconcentration techniques can significantly lower detection limits. Electrothermal atomic absorption spectrometry (ETAAS) provides enhanced sensitivity for low-level Be quantification, further optimized using pyrolytically coated graphite tubes and chemical modifiers such as Mg(NO₃)₂ or Pd(NO₃)₂. Effective separation and preconcentration techniques are essential for reliable Be quantification in complex matrices. Liquid-liquid extraction (LLE), including single-drop microextraction (SDME) and dispersive liquid-liquid microextraction (DLLME), have evolved to reduce the use of hazardous solvents. When combined with ETAAS, surfactant-assisted DLLME using agents like cetylpyridinium ammonium bromide (CPAB) and dioctyl sodium sulfosuccinate (AOT) achieves preconcentration factors of approximately 25, reducing LOD to 1 ng/L. Vesicle-mediated DLLME coupled with ETAAS further enhances sensitivity, allowing detection limits as low as 0.01 ng/L in seawater. Cloud-point extraction (CPE), often employing Triton X-114, facilitates Be extraction using complexing agents or nanomaterials like graphene oxide. These advancements are critical for accurately quantifying Be at ultra-trace levels in diverse environmental and biological samples, overcoming challenges posed by low analyte concentrations and matrix interferences. Full article

Benchmark data are reported for a solid-state laser-based near-infrared spectrometer designed for noninvasive measurements in human skin. These data were obtained using a set of aqueous phantoms composed of polystyrene beads, triton X-100, saline, and glucose. The performance of this prototype solid-state laser platform was compared to parallel results obtained with a Fourier-transform (FT) spectrometer. The fundamental spectroscopic performances of the two spectrometer systems were quantified by an analysis of 100% lines determined by ratioing back-to-back spectra collected over time for each phantom. Root mean square (RMS) noise levels were computed for each dataset and the median RMS noise levels were 327.8 µAU and 667.2 µAU for the FT spectrometer and prototype laser platform, respectively. The analytical utility of the solid-state laser platform was assessed through a series of leave-one-phantom-out partial least squares analyses. Results for the laser prototype data included a standard error of cross validation (SECV) of 7.82 mg/dL for an optimized PLS model with 10 factors over a spectral range of 1401–2238 nm. This compares favorably with the results from the FT spectrometer of an SECV of 6.62 mg/dL with 8 factors and a spectral range of 1551–2378 nm. The additional two PLS factors for the laser prototype were shown to be a consequence of its higher spectral noise. Selectivity of these PLS models was demonstrated by comparing models associated with correct and random glucose assignments to each spectrum. Overall, these findings benchmark the analytical utility of this solid-state laser prototype. Full article

Erythrocytes, the most abundant blood cells, are a prevalent cell model for the analysis of the membrane-damaging effects of different molecules, including drugs. In response to stimuli, erythrocytes can change their morphology, e.g., shape or volume, which in turns influences their main function to transport oxygen. Membrane active molecules can induce hemolysis, i.e., release of hemoglobin into the blood plasma. Free hemoglobin in the blood circulation is toxic causing serious health problems including vasoconstriction, high blood pressure and kidney damage. Therefore, early recognition of the risk of massive hemolysis is highly important. Here, we investigated surfactant induced hemolysis applying UV–vis spectrophotometry. Saponin, sodium dodecyl sulfate and Triton X-100, detergents known to provoke hemolysis at different concentrations and by different mechanisms, were applied to initiate the process. Whole absorption spectra of erythrocyte suspensions in the range 300–750 nm were recorded every 15 s for following the process in real-time. The hemolysis process, with respect to morphological changes in the erythrocytes and their influence on the oxygenation state of hemoglobin, was characterized by the absorbance at 700 nm, the height relative to the background and the wavelength of the Soret peak. The results suggest that these UV–vis spectrophotometry parameters provide reliable information in real-time; not only about the process of hemolysis itself, but also about pre-hemolytic changes in the erythrocytes, even at sub-hemolytic surfactant concentrations. Full article

Copper (II) oxide nanoparticles (CuO NPs) attract much attention as a promising antimicrobial agent. We studied the antibacterial properties of three types of CuO NPs against Escherichia coli bacteria: flake-shaped particles with a diameter of 50–200 nm and a thickness of 10–20 nm (CuO-CD synthesized by chemical deposition), spherical particles with a size of 20–90 nm (CuO-EE obtained by electrical explosion), and rod-shaped particles with a length of 100–200 nm and a diameter of 30 × 70 nm (CuO-CS commercial sample). We tested how the shape, size, and concentration of the NPs, and composition of the dispersion medium affected the properties of the CuO NPs. We prepared dispersions based on distilled water, a 0.9% NaCl solution, and the LB broth by Lennox and used Triton X-100 and sodium dodecyl sulfate (SDS) as stabilizers. The concentration of NPs was 1–100 mg L⁻¹. We showed that the dispersion medium composition and stabilizer type had the greatest influence on the antibacterial effects of CuO NPs. We observed the maximum antibacterial effect for all CuO NP types dispersed in water without a stabilizer, as well as in LB broth with the SDS stabilizer. The maximum inhibition of culture growth was observed under the influence of CuO-EE (by 30%) and in the LB broth with the SDS stabilizer (by 1.3–1.8 times depending on the type of particles). In the saline solution, the antibacterial effects were minimal; in some cases, the CuO NPs even promoted bacterial culture growth. SDS increased the antibacterial effects of NPs in broth and saline but decreased them in water. Finally, among the particle types, CuO-CS turned out to be the most bactericidal, which is probably due to their rod-shaped morphology and small diameter. At the same time, the concentration and aggregation effects of CuO NPs in the colloidal systems we studied did not have a linear action on their antibacterial properties. These results can be used in the development of antibacterial coatings and preparations based on CuO NPs to achieve their maximum efficiency, taking into account the expected conditions of their use. Full article

Vascular graft failure rates remain unacceptably high due to thrombosis and poor integration, necessitating innovative solutions. This study optimized plant-derived extracellular matrix scaffolds as a scalable and biocompatible alternative to synthetic grafts and autologous vessels. We refined decellularization protocols to achieve >95% DNA removal while preserving mechanical properties comparable to native vessels, significantly enhancing endothelial cell seeding. Leatherleaf viburnum leaves were decellularized using sodium dodecyl sulfate-based and Trypsin/Tergitol-based treatments, achieved via clearing in bleach and Triton X-100 for 6 to 72 h. To assess the environmental influence on scaffold performance, leaves from multiple collection sites were processed using sodium dodecyl sulfate-based protocols. Scaffold performance was evaluated through tensile testing and histological analysis to assess structural integrity, while DNA quantification and endothelial cell recellularization measured biological compatibility. Sodium dodecyl sulfate-treated scaffolds with shorter clearing durations demonstrated the highest DNA removal (≥95%) while preserving mechanical properties, significantly outperforming Trypsin/Tergitol treatments. Longer clearing times reduced fiber diameter by 60%, compromising scaffold strength. Shorter clearing times preserved extracellular matrix integrity and significantly improved endothelial cell seeding efficiency. Larger leaves supported significantly higher endothelial cell densities than smaller leaves, highlighting the need for standardized material sources. Permeability tests demonstrated minimal leakage at 120 mmHg and structural stability under dynamic flow conditions, suggesting their suitability for vascular applications. These findings establish a reliable framework for optimizing plant-derived grafts, improving their reproducibility and performance for tissue engineering applications. Full article